Improvement in direct-acting engines



[nua-Liar PATENTED AUG.18, 1868.

@uitrit ftatee getint @frnI WILLIAM D. HOOKER, OF SAN FRANCISCO,l CALIFORNIA.

Leners Patent No. 81,168, dated August 18, 1868.

IMPROVEMENT IN DIRECT-AOTING ENGINES.

To ALL WnoM IT MAY co'NoEnN:

Be it'known that I, WIILLIAM D. HooKEn, of the city and county oi San Francisco, 'Stute of California,` have invented an Improved Direct-Acting'Steam-Engine; and I do-hereby declare the following description and accompanying drawings are sucient to enable anyperson skilled in the art or science to which it` most nearly appertains to make and use my said invention -or improvements without further invention or experiment.

The objectief` my invention is toconstructnn improved direct-acting steam-engine, in which, -by means of two valves, one main and one auxiliary, the steam is caused to act on each end of" the piston in the cylinder,

alternately, without the use of eccentrics, cams, or tappets, while, by the use' of a system of ports, openingatdiiierent parts of' the cylinder and valve-chambers, the valve and piston 'are cushioned at each end of their stroke, in such a manner as to nllowa very high rate of spoed, without the danger of concussion, and more-particularly rendering the engine peculiarly adaptable to direct-acting steam-pumps. l

This is accomplished by the arrangement of an'auxiliary valve, suitable ports connecting the enginecvlinder :ind the valve chamber, and the piston and main valve of a direct-acting engine, in such a manner' that the auxiliary'valve shall open and close the ports leading to theends oi'` the main-valve chamber alternately at each stroke of the piston, by the`action of thesteam supplied and released through the ports', to and fromsaid auxiliary valve, b y thealternate movement of the piston/ andthe 'main valve, thereby supplyingsteam-tolne' end of the main-valve chamber, and'closng communication tothe opposite end, 'the auxiliaryvalve performing` the function of opening one port andA supplying steam to one ebd of the mainyalve, closing communication with the opposite end, thus cushioning or arresting the valve at the end ofi the stroke, small ports being madef in the ends oi' the' main-valve chamber and connecting with the-mainexhausbports, to release the steam at eachl stroke of the main valve,.the exhaust also assisting to complete the stroke ef the valve. j 7

It also consists-in the arrangement of suitable auxiliary ports, in connection-with. the main ports, pistou,

had main valve of' a direct-acting engine, in such amanner that the said auxiliary ports shall be closed bythe main valve when the piston passes the main ports, and thereby cause the piston to be cushioned on the vapo'r confined in the endet' the cylinder,-the main valve performing the functiousof supplying steam .through thed main and auxiliary ports, but releasing steam' through the main ports only, and arrestngthe piston atthe end of its stroke by the valvecovering the auxiliary lports. 4 v i' To more fully explain myinvention, reference is hadto the accompanying-drawings, forming part of this specification, of whichv Figure 1 isa side elevation of my invention. Figure 2-is a side sectional elevation., I Figure 3 is an end sectional view.

Figure 4 is a plan, showing thev main portsand the auxiliary ports and passages.

, Figure 5 is a bottom view of the valve-chamber, showing the position of the ports ou it.

Similar letters of reference in/each ofY the drawings indicate like parts.

a is'the-cylinder and e the'main-valve chamber of my engine,the two, for convenience, being cast separate, and fitted so l'as to allow of the construction of the different ports and passages, -asshowmin iigs. 4 and 5, the two parts being then bolted together, as shown in iig. 1. Between the main-valve chamber and the cylinder is an auxiliary valve,'g, moving in .a chamber at right angles with the main valve, this auxiliary valvebeing' operated alternately from one end to the other of its chamber by steam from the'cylinder, to admit steam from the cylinder to the ends of the main valve.

n are the passages, which admit the steam from the cylinder to the ends of the auxiliury'valv'e, and` which are made to open into the cylinder at such points that it -is impossible for the valveq to be moved until 'the piston has completed a certain portion of its stroke.

The valves may be constructed of any desired form, 'but I prefer a cylindrical one, the central. portion being turned smaller than the ends, to admit steam. The main valve f has two exhaust-ports, one near each end, as shown in fig. 2, and a shallow channel is made in the valve, at the end of each exhaust-port, so that any escaping steam may bc released, and not allowed to find its way behind the valve.

To prevent the valve from turning around, I'place a pin or short stem, '8, near the upper part of the valve, which, working in a corresponding opening, kkeeps the valve always in position. The small ports in the upper portion of the cylinder are kept tight, andV the cylinderv prevented from wearing, by means of recesses in the v bottom of the piston, to allow the steam to press it upwards.

Steam being admitted, the valve standing in the position shown in iig: 2, it willll the main port but not be admitted through it behind the piston which covers the port. But the small port m', which opens behind the piston, also connects with the steam-passage in the valve,I as shown in iigs. 4 and 5, and through this the steam enters and drives the piston to the right, until the'main port z" is opened to admit a full supplyof steam. As the piston continues its motion, the port n is lopened, admitting steam behind theauxiliary valve q, and forcing it into the position shown in iig. 3, thus closing 'the port 1?', s o that when the piston has uncovered it, tho valve q prevents steam from 'passing to the right of the main valve Continuing its motion, the piston opens the port P, and the valve g being in the proper position, steam passes through the port Aand enters behind ,the main valvef, driving it to the right. Whatever steam escapes through the small ports 7c and l' enters the exhaust, j, as shown at iig. 4, while any air or vapor at the right of the valvefis allowed egress through the ports l: and Zuntil the valve passes them, when-it will cushion on the remaining confined vapor. The piston has also passed the port z', and will be cushioned on the remaining steam or vapor at the right, the port m being still closed bythe main valvef. At this instant, the valv'e f has passed to the right, the ports i and mhave been opened, and the piston4 returns in the same manner. As the valve'f moves to the right to change the v motion ofthe piston, the exhaustj is opened, and the'steam from the cylinder passes out through the port i' and jl', and, by its pressure,'keeps up the motion of the valvef until it has completed its'stroke. l

The advantages of my engine are, first, durability, simplicity, and cheapness, there being but threemovi'ng parts in the whole engine, the two valves and the piston; second, certainty of action, starting at4 any point, variable speed from the lowest to the highest, and its adaptability to fire-engines requiring-a highrate of speed; and, thirdly, the ease of inspection, the valve being easily removed by taking off the cover.

Having thus described my invention, what I claim, and desire to secure by Letters Patent, is

1. The auxiliary ports m m', together with the main ports z'z", in combination with the main valve f, piston c, and auxiliary valve g, of a direct-acting engine, constructed substantially as described.

2. The arrangement of the auxiliary valve q, ports p p and n n', in combination with 'the main valvef, and piston e, of a direct-acting engine, constructed substantially as described.

3. In combination with the main valvef, supply-ports i z", exhaust-ports jj', auxiliary valve q, and ports p p', I claim the small ports l Z and t' Je, substantially as herein described. v

In witness whereof, I have hereunto setmy hand and seal.

WILLIAM D. HOOKER. [In s.]

Witnesses J. L. BOONE, C. W. M. SMITH. 

